Polyembryony, Biology

Assignment Help:

Polyembryony

Presence of more than one embryo in a seed is termed polyembryony. The phenomenon, first discovered in orange seeds by Leeuwenhoek (1719), attracted considerable attention because of its potential for application in and horticulture. Polyembryony is broadly classified into simple and multiple, depending on whether the supernumerary arises in one or more embryo sacs in the ovule. Simple polyembryony may be sexual or asexual. In sexual polyembryony embryos may originate from the fertilized egg and synergids, or by budding or cleavage of the polyembryony cells or suspensor of the zygotic embryo.

Asexual embryos are produced within the embryo sac without fertilization. Embryos may also originate from diploid nucellar or integumentary cells of the ode and grow into the embryo sac. These embryos are termed adventive or sporophytic. Multiple polyembryonies involve production of accessory embryos from two or more embryo sacs in the same ovule. For example, in the sea Island cotton, Gossypium barbadense, fertilization of egg in one embryo sac stimulates the induction of embryo from an unfertilized egg in the adjacent embryo sac within the same ovule. Thus, diploid-haploid twin embryos are produced in the seed.


Related Discussions:- Polyembryony

Endocytosis, i have to make assignment on it. can u help me

i have to make assignment on it. can u help me

How is gas exchange done in flatworms, How is gas exchange done in flatworm...

How is gas exchange done in flatworms? Platyhelminthes exchange gases exclusively by diffusion by their body surface. This is only possible because all cells are localized rela

Explain huntington disease gene, Research methods used in studying a geneti...

Research methods used in studying a genetic disease change with technological advances. These changes can be seen in Reading 22.1: Discovering the Huntington Disease Gene, which de

Dot blot, Dot blot  is the technique for measuring the amount of one pertic...

Dot blot  is the technique for measuring the amount of one perticular DNA or RNA in the highly complex mixture. The samples are spotted onto the hybridization membrane (like nitroc

Fats requirements for ulcerative colitis, Q. Fats requirements for ulcerati...

Q. Fats requirements for ulcerative colitis? Usual foods, which contain fats (invisible or inherent fat), are permitted but not fried foods, as they are not easily digested due

Bronchial asthma, Bronchial asthma: Bronchial asthma is characterised ...

Bronchial asthma: Bronchial asthma is characterised by bouts of  dyspnoea as a result of  temporary narrowing of bronchi due to bronchial spasm, mucosal edema and thick secret

Pulmonary valvotomy cardio bypass and use cardioplegia, Pulmonary Valvo...

Pulmonary Valvotomy on Cardio Pulmonary Bypass and use of Cardioplegia :  Single aortic cannulation and separate SVC and IVC cannulation arc done. The cavae are snared to

Explain wild-type fruitfly drosophila melanogaster, A cross among wild-type...

A cross among wild-type fruitfly Drosophila melanogaster  [normal bristles and grey body (s+s, e+ e)] with a mutant fly [short bristles and ebony body (ss ee)] produces following p

Define derived proteins - primary protein derivatives, Define Derived prot...

Define Derived proteins -  Primary Protein Derivatives? Derived proteins are the derivatives of the protein molecule, apparently fonned through hydrolytic changes in the molecu

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd